By Rabiya S. Tuma
Chemobrain-Busters
Peering into the workings of the brain, researchers are starting to unravel the puzzling cognitive changes linked to chemotherapy
By Rabiya S. Tuma
When Alison Lannutti was diagnosed with breast cancer in January 2001, she was a special education teacher in Los Angeles. After her treatment ended, she found that she could no longer handle the stressful routine and mental demands of the job. “Eventually I had to retire on disability,” she says. “I was exhausted and fatigued, and the cognitive impairment was to the point where it was ridiculous. I would be standing there with an overhead projector teaching the continents to the kids, and one kid pointed to a large landmass and asked, ‘What’s that big thing over there?’ and I couldn’t name Greenland.”
Even with a slower schedule, however, Lannutti says she’s scattered and has trouble synthesizing and analyzing information or making effective plans. She now relies on the tricks she taught her students when they had trouble learning or remembering information.
“Before diagnosis, I was a highly functioning professional. I was working full-time teaching special education, and taking classes for my master’s degree,” says Lannutti, who is now 54 and working part-time. Recent neuropsychological tests showed that her cognitive abilities are very uneven, with scores in the 99th percentile in some areas and in the 2nd percentile in others. “It is all these things I know about with my students, but it is me,” she says.
Although Lannutti’s experience is more extreme than that of many cancer survivors, researchers estimate that approximately 20 percent to 25 percent of survivors who were treated with chemotherapy report some cognitive changes, an effect called chemobrain. “There are a variety of reasons why patients may have difficulty with concentration during therapy, but some patients report persistent difficulty with memory and concentration long after treatment ends,” says medical oncologist Patricia Ganz, who runs the LiveStrong Survivorship Center of Excellence at the Jonsson Comprehensive Cancer Center at the University of California, Los Angeles (UCLA). “Those are the ones we are most concerned about.”
The brains of cancer survivors who have symptoms of chemobrain (large illustration) are more activated (yellow-orange)—or working harder—during a memory task than the brains of people who don't have the condition (inset). [Art: Nicolle Rager Fuller]
Survivors of adult cancer have been talking about chemobrain since the mid-1990s, but researchers are only now starting to make sense of the phenomenon. There are no clear answers to the key questions yet—or solutions to the problem—but scientists have uncovered some interesting clues from studies looking at immune system activity in survivors, as well as brain imaging studies.
One confusing aspect of the chemobrain phenomenon is that the patients who complain about chemobrain often do not show problems on neuropsychological tests that assess memory and attention. Janette Vardy illustrated this point when she presented the results of a study from the Princess Margaret Hospital in Toronto at the annual meeting of the American Association for Cancer Research (AACR) in April. Vardy, who is now a researcher at the University of Sydney in Australia, and her colleagues tested three groups of women: patients who had received chemotherapy and complained about cognitive problems, patients who had received chemotherapy but did not notice cognitive changes, and patients who had only local therapy, such as radiation and surgery. All of the patient groups performed about the same on the neuropsychological tests.